Impact-tool



No. 622,165. Patened Mar. 2s, |899.

\ T. H. PHILLIPS.

IMPACT TOOL.

(Application :Bled Oct. 25, 1898.) (No Model.) 4 Sheets-Sheet I.

zo A9 /Z zzgl No. 622,!65. Patented Mar. 28, |899.

` y T. H. PHILLIPS.

IMPACT TOOL.

(Application filed Oct. 25, 189B.) (No Model.) 4 Sheets-Sheet 2.

W w www?? we @mams PETERS cu.. PHoTc-Llmo.. wAsHmm'oN. n. c,

No. 622,165. Patented Mar. 28, |899.

T. H. PHILLIPS.

IMPACT TOUL.

(Application med ou. 25, 189s.) (No Model.) 4 Sheets-Sheet 3.

Patented Mar. 28, I899.

Nu. 622,|s5.

T. H. PHILLIPS.

IMPACT TO0L.`

(Application led Oct. 25, 1898.)

4 Sheets-Sheet 4.

(No Model.)

my m Evans co, Pnmuho.. WASHINGTON n c Nrran STATES 'PATENT @FincaTHOMAS II. PHILLIPS, OF ST. DAVIDS, PENNSYLVANIA.

INI PACT-TOO L.

SPECIFICATION forming' part of Letters Patent No. 622,165, dated March28,A 1899.

Application tiled October 25,1898. Serial No.694 ,531. (No model.)

T0 all zzz/1,0m t may concern:

Be it known that I, THOMAS H. PHILLIPs, a citizen of the United States,residing in St. Davids,Delaware county, Pennsylvania,have inventedcertain Improvements in Impact- Tools, of which the following is aspecification.

My invention relates to impact-tools, such as rock-driils,my improvementbeing directed mainly to thevalves and valve-controlled passages of thetool and to the rod-packing devices carried by the cylinder front head.

The objects of my improvements in the valve mechanism are to avoidexcessive wear and friction in the steam-chest, to provide for avariable stroke of the piston, to overcome the inertia of a heavy singlevalve, and

-thereby insure a quicker and more sensitive action of the valvemechanism, to employ interchangeable valves, to cushion the rear strokeof the piston, so as to prevent it from coming into injurious contactwith the back head, to prevent cushioning of the forward stroke, so asto insure an uncushioned blow, and to regulate the speed and time oftravel of the valve governing the ow of motive fluid to and from theforward end of the cylinder without affecting the flow of motive iiuidto and from the rear end of said cylinder.

The objects of the impro vements in the rodpacking devices are to reducethe wear on the packing,to avoid the trouble and delay caused by thejarring loose of the nuts, such as are sometimes used to hold the glandin place, to

prevent the gland from falling out of position, and to provide fordrawing the gland up evenly, so as to uniformly compress the packingwhen desired.

In the accompanying drawings, Figure 1 represents a longitudinalsectional view of an impact-tool constructed in accordance with myinvention. Fig. 2 is a plan view of the same with the valve-chest andvalves in section. Fig. 2@L is an enlarged sectional view of one of thevalves. Fig. 3 is a transverse section on the line fr, Fig. 1. Fig. 4 isa view of the under side of the valve-chest structure, showing thepassages formed therein. Figs. 5, 6, 7, and 8 are diagrams illustratingsuccessive positions of the piston and the position of the valvescorresponding therewith,

and Figs. 9, 10, and 11 are diagrams illustrating modifications of partof theinvention.

1 represents the cylinder of the tool, which contains an elongatedpiston comprising a forward head 2, a rear head 3, and an interveninggrooved or chambered portion 4, the piston-rod 5 passing through astuffing-box carried by the cylinder front head 6, to which referencewill be made hereinafter.

The rear head 7 of the cylinder has the usual ratchet mechanismconnected with a spirallygrooved bar 8, which engages with a nut orprojection inside of the piston, so that the latter will be partiallyturned on its axis on each backward stroke. This mechanism forms no partof my present invention and may be similar to any of the formsordinarily employed. l

The valve-chest 9 is securely bolted to the top or side of the cylinderland contains two valve-chambers disposed side by side, one of thesechambers containingavalve 10 and the other a precisely similar valve 1l.Each of the valves 10 and 11 is a spool-like structure consisting of astem with projecting iianges or heads 12 and 13 at the opposite endsanda central ange 14 between the ends, the annular space between theheads 12 and 14 of each valve communicating with the forward end of thechamber in which said valve works through a passage 15 of contracteddiameter in the valve-stem and said space also communicating with therear end of the chamber in which the valve works through a likecontracted passage 17 in the valve-stem. I Each end of eachvalve-chamber is enlarged in diameter for the reception of a washer 19,which closes the end of that portion of the valve-chamber in which thevalve reciprocates, rubber or other elastic material 2O being interposedbetween this washer and the end cap 21 of the valve-chest, so as toprovide an elastic backing for the washer.

The annular space between the heads 12 and 14 of each valve is inconstant communication with a steam-inlet passage 22, which has athreaded opening at each side of the valve-chest, so that a steam-supplypipe can be connected to said chest at either side, and in like mannerthe annular space between the heads 13 and 14 of each valve is inconstant communication with an exhaust-passage 23, which likewise has athreaded opening at each side of the valve-chest for the reception of anexhaust-pipe. The openings not in use are suitably plugged.

Between the inlet and exhaust passages of the valve-chest are locatedtwo passages 24 and 25, the passage 2a communicating with the chambercontaining the valve 10 and the passage 25 communicating with thechamber which contains the valve 11, and said passage 21 is incommunication through a passage 26 with the rear end of the cylinder 1,while the passage 25 is in communication through a passage 27 with thefront end of said cylinder. In the cylinder is also formed a U -shapedpassage 28,the ends of which communicate with the interior of thecylinder, and this passage is in constant communication with theexhaust-passage of the valvechest through a passage 29. The forward endof the chest containing the valve 10 is in communication with theinterior of the cylinder through a passage 30, formed partly in thecylinder and partly in the valve-chest-,and the rear end of saidvalve-chest is also in communication with the interior of the cylinderthrough a passage 31. The rear end of the chamber containing the valve11 vis in communication with the passage 2G of the lcylinder through apassage 32, formed partly in the cylinder and partlyin the under side ofthe valve-chest, and the forward end of said valve chamber is incommunication through a passage 33 on the under side of the valve-chestwith the chamber containingthe I valve 10, this communication being at apoint in said chamber between the rear end of the same and theexhaust-passage 23.

The operation of the tool is as follows, the motive fiuid forconvenience being considered to be steam: Supposin g, in the firstplace, the parts to be in the position shown in Fig. 5- that is to say,the piston at the rear end of its stroke, the valve 10 at the rear endof its stroke, and the valve 11 at the forward end of Aits stroke-steamis entering the rear end of the cylinder from the steam-inlet passage 22through the forward space of the valve 10 and through the passages 2aand 2G, and steam is escaping from the forward end of the cylinderthrough the passages 27 and 25, the rear space of the valve 11, and theexhaust-passage 23. Steam can always enter each end of eachvalve-chamber from the steam-passage 22 through the passages 15 and 17in the valve-stem, and the movement of each valve in its chamber iscaused by cutting off the escape of steam from one end of saidvalve-chamber and at the same time permitting the escape of steam fromthe opposite end of said valve-chamber. The valves are retained in theposition shown in Fig. 5, owing to the fact 'that there is fullsteam-pressure exerted on the front end of the valve 10, because thepassage 30 is closed by the forward head 2 of the piston, while the rearend of the chamber containing said valve 10 is open to the exhaustthrough the passage 81, the central groove of the piston, and thepassages 28 and 29, and the rear end of the chamber containing the valve11 is open to the full, pressure steam in the passage 2G, as well as tothat which enters through the passage 17 in the valve-stem, While thefront end of said chamber is open to the exhaust through the passage 33and the rear-space of the valve 10. This condition of affairs continuesuntil the piston moves forwardly in the cylinder to the position shownin Fig. G-that is to say, until its rear head 3 closes the passage 31and the front head 2 uncovers the passage 30. There being now a freeescape of steam from the chamber in front of the valve 10 and the escapeof steam from the rear end of said chamber being cut olf, the valve 10by the accumulation of steam at its rear end is moved forwardly to theposition shown in Fig. 6, so as to cut oif the supply of steam to therear end of the cylinder and open said rear end of the cylinder to theexhaust, and at the same time the rear head of the valve 10 cuts olf theexhaust of steam from the front end of the chamber containing the valve11 by reason of the fact that said rear head of the valve 10 isinterposed between the opening of the passage 33 and the exhaust-passage23. As the steam exhausts from the rear end of the cylinder the pressurein the passage 20 and in the rear end of the chamber containing thevalve 11 is reduced and is finally overcome by the pressure in the frontend of said chamber, whereupon the valve 11 is moved rearwardly, asshown in Fig. 7, so as to open communication between the front end ofthe cylinder and the steam-inlet passage 22 through the front space ofthe valve 11 and the passages 25 and 27. Owing to the delay in themovement of the valve 11, however, the admission of steam to the forwardend of the cylinder does not take place until an appreciable time haselapsed after the opening of the rear end of the cylinder to the exhaustby the movement of the valve 10. Hence the piston has moved forwardly inthe cylinder to the full extent necessary to cause the tool to deliverits blow before steam enters the forward end of the cylinder. Anuncushioned blow is the result and time has been allowed for the exhaustfrom the rear end of the cylinder and back pressure is thus avoided onthe retraction of the piston. As the piston moves rearwardly and thevalves retain the position shown in Fig. 7 until said piston reaches theposition shown in Fig. 8-that is to say, until the front head 2 closesthe passage 30 and the rear head 3 opens the passage 31. Escape of steamfrom the rear end of the chamber containing the valve 10 being thuspermitted and escape of steam from the front end of said chamber beingcut oif, the valve 10 moves rearwardly again, admitting steam to therear end of the cylinder and opening to the exhaust the front end of thechamber containing the valve 1l,

IOO

IIO

so that the pressure of live steam against the rear end of -said valvewill immediately eifect the forward movement of the same, thus openingthe forward end of the cylinder to the exhaust, this admission of steamto the rear end of the cylinder and exhaust from the front end beingeffected at such a point in the rearward travel of the piston that amplecushioning of the rear stroke is provided for and injurious contact ofthe piston with the rear head of the cylinder is prevented. By thususing two valves, one controlling the flow of steam to and from the rearend of the cylinder and the other controlling the flow of steam to andfrom the front end of the cylinder and by making the movement of thelatter valve dependent upon the previous movement'of the former Ipositively insure the attainment of the uncushioned forward stroke andcushioned back stroke of the piston, the use of the two valves alsoenabling me to make each valve so light that it has less inertia, andthus is more sensitive than a single heavier valve. Each valve,moreover, being free to turn and perfectly balanced, excessive wear andfriction are avoided, and both valves being precisely alike thesubstitution of one for the other by an ignorant or careless attendantcannot affect the working of the tool. Variable stroke ofthe piston isalso provided for, since it'will be apparent that the tool will loeoperative so long as the forward stroke permitted is sufficient to causethe forward head of the piston to uncover the passage 30 and the rearhead to cover the passage 3l, the back stroke in this case beingcorrespondingly limited owing to the restricted volume of steam which ispermitted to enter the forward end of the cylinder. Hence the pistonwill simply reciprocate with a short stroke in midposition, a longerstroke being provided for by moving the cylinder rearwardly on itssupporting structure.

Secured to the front end of the cylinder is a split and separable fronthead or casing 6, held together by transverse bolts 36 37 and having atthe inner end a split and separable plug 38, which lits into the forwardend of the bore of the cylinder, the forward end of the said casingbeing internally threaded for the reception of an external thread upon agland or follower 39, which is likewise by preference split andseparable, so that it can be readily applied to the piston-rod 5. A massof packing 40 is interposed between the inner end of this gland 39 andthe plug 38. Hence by screwing up the gland this mass of packing can becompressed to the desired extent, the pressure being exerted evenlythroughout the mass instead of unevenly, as is sometimes the case whenthe gland or follower has projecting ears acted upon by in' dependenttightening devices, one of which can be screwed tighter than the other.The

forward end of the split casing 6 is slotted, as shown in Figs. 2 and 3,so that this portion can by the action of the bolts 37 be caused to bindtightly upon the gland or follower 39, and thus lock the same inposition after adj ustment. In case, however, there should be anyloosening or backing off of this gland the complete release of the samefrom the casing 6 is prevented by the engagement of an external shoulder41 upon the gland with an internal shoulder 42 in the casing, so thatunder no circumstances can the gland drop from the casing and fall intothe hole which is being drilled, an accident which sometimes happenswhen the ordinary gland with studs and nuts is employed and which islikely to cause such jamming of the drilling-tools in the hole as tomake their withdrawal difficult and sometimes necessitate theirabandonment.

It will be observed that-the packing is disposed close to the jointbetween the cylinder and the front head-in other words, as close aspossible to the piston, where there is the least vibration of thepiston-rod, and consequently the least wear upon the packing. Hence thelatter will remain in good condition for a longer time than packingdisposed more or less in advance in the front head, where the vibrationof the piston-rod is more appreciable.

When it is desired to repack the stuffingbox, this can be readilyeffected by removing the nuts from one or other of the ends of thelongitudinal bolts 35, whereby the opposite heads are secured to thecylinder, and then sliding the head 6 forward on the -rod 5 until theplug 38 can be freed from engagement both with the cylinder and head,the parts of the plug being then separated, so as to permit access tothel interior of the stuffing-box. After the latter has been repackedthe parts of the plug can be reapplied to the rod and the head 6 againsecured in position.

The casing 6, plug 38, and gland 39 are made in split and separablehalves, because it is preferable in this class of tools to forge IOO IIO

from one piece of metal the piston, the piston-rod, and the chuck inwhich the shank of the drill-steel is clamped, the chuck, as well as thepiston, being of greater diameter than the rod, so that the lattercannot be passed longitudinally through the plug or gland. When the rodis keyed or otherwise detachably secured to the piston or chuck,however, the split construction of the parts through which the rodpasses need not necessarily be adopted.

The use of the passages 15 and 17 in the valves for maintaining constantcommunication of each end of each valve-chamber with thelive-steampassage is not essential to the proper carrying out of my invention, asit is manifest that the same end can be attained by the use of passagesin the valve-chestas, for instance, the passages l5fL and 17a. (Shown inFig; 9.) In fact, the maintenance of constant live steam communicatingwith each end of the chamber containing the valve l1 .is not necessary,as steam may, if desired,

be conducted to and from the opposite ends of said chamber solelythrough the medium of the passages 32 and 33 under control of the valvelO, and the entrance of live steam to the forward end of the chambercontaining the valve lO may be effected by permitting a slight clearancebetween the forward head of said valve and the chest instead of byapassage through the valve. These modifications are illustrated in Fig.l0. The construction shown in Figs. l and 2, however, is

Y preferred, as it permits me to use snug-fitting valves and renders thevalves interchangeable.

The rear end of the chamber containing the valve 1l may, if desired,like the front end, communicate directly with the chamber containing thevalve lO-as shown, for instance, at 32 in Fig. 10-instead ofcommunicating indirectly through the medium of the passages l and 2G, asshown in Figs. 5 to 8, the end to be attained being the placing of saidpassages 32 and '33 in communication with the live-steam and exhaustpassages of the chest alternately or the alternate closing of eachpassage and the opening of the same to the exhaust and the constructionshown in Figs. l, 2, and 4 being adopted simply for convenience, as itavoids the formation of complicated passages in the valve-chest, whichwould otherwise be required.

The advantages of my invention, so far as they arise from the use of twolight, independent, and easily-operated valves, one for controlling theflow of steam to and from the front end of the cylinder and the otherfor controlling the flow of steam to and from the rear end of thecylinder, may be attained, even if the lnovement of thefront-cnd-controlling valve is not dependent upon the previous movementof the rear-end-controlling valve. In the structure shown in the diagramFig. 1l, for instance, the passages 32b and 33b lead directly to thecylinder, the termination of the passage 33h being some distance inadvance of that of the passage 3l and the termination of the passage 32being some distance in advance of that of the passage 30, so that bothsets of' passages will be controlled by the piston. lf this constructionis adopted, the movement of the valve ll will follow that of the valvelO on the forward stroke of the piston, so as to obtain the same resultsof uncushioned blow and free rear exhaust which arise from the preferredconstruction shown in Figs. l to S; but the movement of the valve 1lwill in this case precede that of the valve l0 on the back stroke of thepiston. Hence as compared with the preferred construction there will bean earlier cut off of the steam from the front end of.

the cylinder and consequent lessened lifting power, decreased reartravel of the piston, and a lighter blow.

Having thus described my invention, I claim and desire to secure byLetters' Patentl. The combination in an im pact-tool, of a cylinder, areciprocating piston contained therein, a valve-chest having inlet andexhaust passages for the motive fluid, and two valves each in its ownchamber and each operated by the pressure of the motive fluid, one valvecontrolling the flow of motive fluid to and from the rear end of thecylinder and the other valve controlling the flow of motive fluid to andfrom the front end of the cylinder, substantially as specified.

2. The combination in an impact-tool, of a cylinder, a reciprocatingpiston contained therein, a valve-chest having inlet and cxhaustpassages for the motive fluid, and two valves, each in its own chamber,one valve controlling the flow of motive fluid to and from the rear endof the cylinder and the other Valve controlling the flow of motive fluidto and from the front end of the cylinder, the movement of saidfront-end-controlling valve being governed by and following thelnovement of said rear-end-controllin g valve, substantially asspecified.

3. The combination in an impact-tool, of the cylinder, a reciprocatingpiston therein, a valve-chest having inlet and exhaust passages for themotive fluid, and two valves, each in its own chamber, one of saidvalves controlling the flow of motive fluid to and from the rear end ofthe cylinder and the other controlling the flow of motive fluid to andfrom the forward end of the cylinder, the movement of saidrear-end-controlling valve being governed by the movement of the pistonand the movement of said front-end-controlling valve being governed byand following the movement of the rear-end-controlling valve,substantially as specified.

4. The combination of the cylinder, a reciprocating piston therein, aValve-chest having inlet and exhaust passages for the motive fluid, twovalves each in its own chamber, a passage leading from the firstvalve-chamber to the rear end of the cylinder, a passage leading fromthe second valve-chamber to the front end of the cylinder, each passage,by the movement of its controlling-valve, being placed in communicationalternately with the inlet and exhaust passages of the chest, andpassages for admitting motive fluid to and exhausting it from theopposite ends of each valve-chest, said passages being so disposed thaton the forward movement of the piston in the cylinder, the first valvewill be moved so as to open the rear end of the cylinder to the exhaust,and the second valve will be subsequently moved, so as to open the frontend of the cylinder to the inlet, substantially as specified.

5. The combination of the cylinder, a reciprocating piston therein, avalve-chest having inlet and exhaust passages for the motive fluid, twovalves, each in its own chamber, a passage leading from the firstvalve-chamber to the rear end of the cylinder, a passage leading fromthe second valve-chamber to I OO IOS

IIO

the front end of the cylinder, each passage, by the movement ot' itscontrolling-valve, being placed in communication alternately with theinlet and exhaust passages of the chest, and passages for admittingmotive fluid to and exhausting it from the opposite ends ot' eachvalve-chest, said passages being so disposed that on the forwardmovement of the piston in the cylinder, the first valve will be' movedso as to open the rear end of the cylinder to the exhaust, and thesecond Valve will be subsequently moved, so as to open the front end ofthe cylinder to the inlet, and on the rearward movement of the piston inthe cylinder, the first valve will be moved so as to open the rear endof the cylinder to the inlet, and the second valve will be subsequentlymoved so as to open the front end of the cylinder to the exhaust,substantially as specified.

6. The combination of the cylinder, a reciprocating piston therein, avalve-chest having inlet and exhaust passages for the motive fluid, twovalves each in its own chamber, a passage leading from the firstvalve-chamber to the rear end of-the cylinder, apassage leading from thesecond valve-chamber to the front end of the cylinder, each passage, bythe movement of its controlling-valve, being placed in communicationalternately with the inlet and exhaust passages of the chest, passagesleading from the opposite ends of the first valve-chamber to thecylinder so as to be controlled by the piston, and passages leading fromthe opposite ends of the second valve-chamber to the firstvalve-chamber, so as to be controlled by the valve in said chamber,substantially as specified.

7. The combination of the cylinder, a reciprocating piston therein, avalve-chest having inlet and exhaust passages for the motive fiuid, twovalves each in its own chamber, a passage leading from the firstvalve-chamber to the rear end of the cylinder, a passage leading fromthe second valve-chamber to the front end of the cylinder, each passage,by the movement of its controlling-valve, being placed in communicationalternately with the inlet and exhaust passages of the chest, passagesleading from the opposite ends of the first valve-chamber to thecylinder so as to -be controlled by the piston, passages leading fromthe opposite ends of the second valvechamber to the first valve-chamber,so as to be controlled by the valve in said chamber, and passageswhereby motive iiuid is continuously admitted to the opposite ends ofsaid rst valve-chamber, substantially as specified.

8. The combination of the cylinder, a reciprocating piston therein, avalve-chest having inlet and exhaust passages for the motive fluid, twovalves each in its own chamber, a passage leading from the firstvalve-chamber to the rear end of the cylinder, a passage leading fromthe second valve-chamber to the front end of the cylinder, each passage,by the movement of its controlling-valve, being placed in communicationalternately with the inlet and exhaust passages of the chest, andpassages leading from the opposite ends of the first valve-chamber tothe cylinder so as to be controlled by the piston, passages leadingyfrom the opposite ends of the second valveto the rear end of thecylinder, a passage leading from the second valve-chamber to the frontend of the cylinder, each passage, by the movement of itscontrolling-valve, being placed in communication alternately with theinlet and exhaust passages of the chest, passages leading from theopposite ends of the first valve-chamber to the cylinder so as to becontrolled by the piston, passages leading from the opposite ends of thesecond valvechamber to the first valve-chamber so as to be controlled bythe valve in said chamber, and passages in the valves, whereby each endof each valve-chamber is continuously in communication with themotive-fluid-inlet passage, substantially as specified.

10. The combination of thecylinder, piston and piston-rod of animpact-tool, with a stuffing-box casing having an internal shoulder, anda gland for compressing the packing, said gland having an externalshoulder located inside of the shoulder of the stuffing-box and adaptedto engage with the internal shoulder of the casing to prevent removal ofthe gland, substantially as specified.

1l. The combination of the cylinder,piston, and piston-rod of animpact-tool, with a split and separable stuffing-box casing having aninternal shoulder, and a gland or follower contained within said casingand having an external shoulder located inside of the shoulder of thestuffing-box and adapted to engage with that of the casing,substantially as specified.

l2. The combination of the cylinder,piston, and piston-rod of animpact-tool, with a split and separable stuffing-box casing slotted atthe forward end, a gland screwed into said casing, and transverse boltswhereby the slotted portion of the casing is confined to said gland,substantially as specified.

13. The combination of the cylinder,piston, and piston-rod of animpact-tool, with a split and separable stuffing-box casing having aninternal shoulder, and a split and separable gland or follower fitted tosaid stuffing-box and having an external shoulder for engaging with thatof the casing, substantially as specifled.

14. The combination of the cylinder,piston, and piston-rod of animpact-tool, with a stuff- IOO IIO

ing-box for engaging with that of the casing, and a split and separableplug located at the inner end of said stufling-box easing, suhstantiallyas specified.

In testimony whereof I have signed my name to this'speeiication in l[hepresence of two subscribing witnesses.

THOMAS Il. PIIILLPS.

Vitnesses:

WILL. A. BARR, Jos. II. KLEIN.

